Leak in large dura-skrim liner at the bulkhead. Tape?

[Richard Hasting]

Hey everyone. I have a large DWC that is lined with Dura-Skrim.

The bed is lined with 2X10, and I am using a 2" bulkhead fitting.

I have two fittings. One is leak free. The second is leaking pretty badly.

I do not have the option of moving the bulkhead. 

Suggestions?

Thanks

Richard Hasting